Hello.
I recommend you to pay attention to 888. This is a great beginner site that has good conditions for new players and lots of interesting daily freerolls. The minimum deposit is $ 10.
It depends from which country you are and if the online poker market is regulated or not. If it is regulated like in my country i would try to stick with the officially allowed operators and avoid grey market ones. After that you should check where are the best offers for first deposit. If you do not want to spend money you can also use CC freerolls to build initial bankroll.